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Prevalence of vegetation browning in China’s drylands under climate change 被引量:1
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作者 li fu Guolong Zhang +3 位作者 Jianping Huang Ming Peng Lei Ding Dongliang Han 《Geography and Sustainability》 CSCD 2024年第3期405-414,共10页
Vegetation greening has long been acknowledged,but recent studies have pointed out that vegetation greening is possibly stalled or even reversed.However,detailed analyses about greening reversal or increased browning ... Vegetation greening has long been acknowledged,but recent studies have pointed out that vegetation greening is possibly stalled or even reversed.However,detailed analyses about greening reversal or increased browning of vegetation remain scarce.In this study,we utilized the normalized difference vegetation index(NDVI)as an indicator of vegetation to investigate the trends of vegetation greening and browning(monotonic,interruption,and reversal)through the breaks for the additive season and trend(BFAST)method across China’s drylands from 1982 to 2022.It also reveals the impacts of ecological restoration programs(ERPs)and climate change on these vegetation trends.We find that the vegetation displays an obvious pattern of east-greening and west-browning in China’s drylands.Greening trends mainly exhibits monotonic greening(29.8%)and greening with setback(36.8%),whereas browning shows a greening to browning reversal(19.2%).The increase rate of greening to browning reversal is 0.0342/yr,which is apparently greater than that of greening with setback,0.0078/yr.This research highlights that,under the background of widespread vegetation greening,vegetation browning is pro-gressively increasing due to the effects of climate change.Furthermore,the ERPs have significantly increased vegetation coverage,with the increase rate in 2000-2022 being twice as much as that of 1982-1999 in reveg-etation regions.Vegetation browning in southwestern Qingzang Plateau is primarily driven by adverse climatic factors and anthropogenic disturbances,which offset the efforts of ERPs. 展开更多
关键词 China’s drylands Ecological restoration programs Climate change Greening to browning reversal BFAST
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Multi-Granularity Neighborhood Fuzzy Rough Set Model on Two Universes
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作者 Ju Wang Xinghu Ai li fu 《Journal of Intelligent Learning Systems and Applications》 2024年第2期91-106,共16页
The two universes multi-granularity fuzzy rough set model is an effective tool for handling uncertainty problems between two domains with the help of binary fuzzy relations. This article applies the idea of neighborho... The two universes multi-granularity fuzzy rough set model is an effective tool for handling uncertainty problems between two domains with the help of binary fuzzy relations. This article applies the idea of neighborhood rough sets to two universes multi-granularity fuzzy rough sets, and discusses the two-universes multi-granularity neighborhood fuzzy rough set model. Firstly, the upper and lower approximation operators are defined in the two universes multi-granularity neighborhood fuzzy rough set model. Secondly, the properties of the upper and lower approximation operators are discussed. Finally, the properties of the two universes multi-granularity neighborhood fuzzy rough set model are verified through case studies. 展开更多
关键词 Fuzzy Set Two Universes Multi-Granularity Rough Set Multi-Granularity Neighborhood Fuzzy Rough Set
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Application of next-generation sequencing technology to precision medicine in cancer: joint consensus of the Tumor Biomarker Committee of the Chinese Society of Clinical Oncology 被引量:16
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作者 Xuchao Zhang Zhiyong liang +47 位作者 Shengyue Wang Shun Lu Yong Song Ying Cheng Jianming Ying Weiping liu Yingyong Hou Yangqiu li Yi liu Jun Hou Xiufeng liu Jianyong Shao Yanhong Tai Zheng Wang li fu Hui li Xiaojun Zhou Hua Bai Mengzhao Wang You Lu Jinji Yang Wenzhao Zhong Qing Zhou Xuening Yang Jie Wang Cheng Huang Xiaoqing liu Xiaoyan Zhou Shirong Zhang Hongxia Tian Yu Chen Ruibao Ren Ning liao Chunyan Wu Zhongzheng Zhu Hongming Pan Yanhong Gu liwei Wang Yunpeng liu Suzhan Zhang Tianshu liu Gong Chen Zhimin Shao Binghe Xu Qingyuan Zhang Ruihua Xu lin Shen Yilong Wu 《Cancer Biology & Medicine》 SCIE CAS CSCD 2019年第1期189-204,共16页
Next-generation sequencing(NGS) technology is capable of sequencing millions or billions of DNA molecules simultaneously.Therefore, it represents a promising tool for the analysis of molecular targets for the initial ... Next-generation sequencing(NGS) technology is capable of sequencing millions or billions of DNA molecules simultaneously.Therefore, it represents a promising tool for the analysis of molecular targets for the initial diagnosis of disease, monitoring of disease progression, and identifying the mechanism of drug resistance. On behalf of the Tumor Biomarker Committee of the Chinese Society of Clinical Oncology(CSCO) and the China Actionable Genome Consortium(CAGC), the present expert group hereby proposes advisory guidelines on clinical applications of NGS technology for the analysis of cancer driver genes for precision cancer therapy. This group comprises an assembly of laboratory cancer geneticists, clinical oncologists, bioinformaticians,pathologists, and other professionals. After multiple rounds of discussions and revisions, the expert group has reached a preliminary consensus on the need of NGS in clinical diagnosis, its regulation, and compliance standards in clinical sample collection. Moreover, it has prepared NGS criteria, the sequencing standard operation procedure(SOP), data analysis, report, and NGS platform certification and validation. 展开更多
关键词 Next-generation SEQUENCING TECHNOLOGY CANCER consensus
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miR-21 promotes the differentiation of hair folliclederived neural crest stem cells into Schwann cells 被引量:9
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作者 Yuxin Ni Kaizhi Zhang +5 位作者 Xuejuan liu Tingting Yang Baixiang Wang li fu Lan A Yanmin Zhou 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第8期828-836,共9页
Hair follicle-derived neural crest stem cells can be induced to differentiate into Schwann cells in vivo and in vitro. However, the underlying regulatory mechanism during cell differentiation remains poorly understood... Hair follicle-derived neural crest stem cells can be induced to differentiate into Schwann cells in vivo and in vitro. However, the underlying regulatory mechanism during cell differentiation remains poorly understood. This study isolated neural crest stem cells from human hair folli-cles and induced them to differentiate into Schwann cells. Quantitative RT-PCR showed that microRNA (miR)-21 expression was gradually increased during the differentiation of neural crest stem cells into Schwann cells. After transfection with the miR-21 agonist (agomir-21), the differentiation capacity of neural crest stem cells was enhanced. By contrast, after transfection with the miR-21 antagonist (antagomir-21), the differentiation capacity was attenuated. Further study results showed that SOX-2 was an effective target of miR-21. Without compromising SOX2 mRNA expression, miR-21 can down-regulate SOX protein expression by binding to the 3′-UTR of miR-21 mRNA. Knocking out the SOX2 gene from the neural crest stem cells significantly reversed the antagomir-21 inhibition of neural crest stem cells differentiating into Schwann cells. The results suggest that miR-21 expression was increased during the differentiation of neural crest stem cells into Schwann cells and miR-21 promoted the differentiation through down-regu-lating SOX protein expression by binding to the 3′-UTR of SOX2 mRNA. 展开更多
关键词 nerve regeneration microRNA stem cells Schwann cells SOX2 hair follicle neuralcrest stem cells NEURONS NSFC grant neural regeneration
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一种自适应扩展卡尔曼滤波的永磁同步电机无位置传感器矢量控制 被引量:3
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作者 兰志勇 李延昊 +2 位作者 罗杰 李福 戴珊琪 《电机与控制学报》 EI CSCD 北大核心 2024年第3期141-148,共8页
在粗差干扰或噪声统计偏差情况下,扩展卡尔曼滤波(EKF)对永磁同步电机(PMSM)的速度和转子位置估计存在精度下降问题,为此提出一种基于新息序列的自适应扩展卡尔曼滤波算法(AEKF)。首先,将粗差干扰加入系统观测方程中,分析粗差干扰对系... 在粗差干扰或噪声统计偏差情况下,扩展卡尔曼滤波(EKF)对永磁同步电机(PMSM)的速度和转子位置估计存在精度下降问题,为此提出一种基于新息序列的自适应扩展卡尔曼滤波算法(AEKF)。首先,将粗差干扰加入系统观测方程中,分析粗差干扰对系统观测精度的影响。其次,为增强算法的抗扰性能,在新息协方差计算中设置加权系数,通过调整临近时刻的新息协方差阵权重,计算出新息协方差值,并更新到卡尔曼增益的计算。最后,建立AEKF数学模型,并对比粗差干扰与噪声统计出现偏差情况下,AEKF与EKF两种策略的观测性能。仿真和实验结果表明,在粗差干扰或噪声统计信息出现偏差情况下,AEKF算法对永磁同步电机转速的观测具备更强的鲁棒性及更高的预测精度。 展开更多
关键词 永磁同步电机 转子位置与速度估计 无位置传感器 自适应扩展卡尔曼滤波 矢量控制
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Recent Advances of Graphitic Carbon Nitride-Based Structures and Applications in Catalyst, Sensing, Imaging, and LEDs 被引量:10
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作者 Aiwu Wang Chundong Wang +2 位作者 li fu Winnie Wong-Ng Yucheng Lan 《Nano-Micro Letters》 SCIE EI CAS 2017年第4期108-128,共21页
The graphitic carbon nitride(g-C_3N_4) which is a two-dimensional conjugated polymer has drawn broad interdisciplinary attention as a low-cost, metal-free, and visible-light-responsive photocatalyst in the area of env... The graphitic carbon nitride(g-C_3N_4) which is a two-dimensional conjugated polymer has drawn broad interdisciplinary attention as a low-cost, metal-free, and visible-light-responsive photocatalyst in the area of environmental remediation. The g-C_3N_4-based materials have excellent electronic band structures, electron-rich properties, basic surface functionalities, high physicochemical stabilities and are ‘‘earth-abundant.'' This review summarizes the latest progress related to the design and construction of g-C_3N_4-based materials and their applications including catalysis, sensing,imaging, and white-light-emitting diodes. An outlook on possible further developments in g-C_3N_4-based research for emerging properties and applications is also included. 展开更多
关键词 Graphitic carbon nitride(g-C3N4) CATALYSIS SENSING IMAGING LED
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Mitochondrial localization of ORF346 causes pollen abortion in alloplasmic male sterility 被引量:7
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作者 Shifei Sang Hongtao Cheng +8 位作者 Mengyu Hao Bingli Ding Desheng Mei Hui Wang Wenxiang Wang Jia liu li fu Kede liu Qiong Hu 《The Crop Journal》 SCIE CSCD 2021年第6期1320-1329,共10页
The Nsa cytoplasmic male sterility(CMS) system confers stable male sterility and offers great potential for production of hybrid seeds in oilseed rape. However, genes responsible for male sterility in Nsa CMS have not... The Nsa cytoplasmic male sterility(CMS) system confers stable male sterility and offers great potential for production of hybrid seeds in oilseed rape. However, genes responsible for male sterility in Nsa CMS have not been identified. By mitochondrial genome sequencing of Nsa CMS and its maintainer line,we identified in an Nsa CMS line several chimeric genes encoding hypothetical proteins harboring transmembrane domains. One novel chimeric gene orf346 showed high identity with cox1 at the 50 terminal region and was co-transcribed with nad3 and rps12 genes. Transgenic plants of orf346 fused with or without mitochondrial targeting peptide conferred complete male sterility in Arabidopsis. ORF346 was mitochondrion-localized. Expression of orf346 in Escherichia coli inhibited bacterial growth, with excessive accumulation of reactive oxygen species and decreased ATP content. These results reveal a link between the newly identified mitochondrial gene orf346 and the abortion of Nsa CMS. Inadequate energy supply and excessive accumulation of reactive oxygen species may account for pollen abortion in Nsa CMS plants. 展开更多
关键词 Brassica napus Cytoplasmic male sterility Orf346 Reactive oxygen species ATP
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A lignified-layer bridge controlled by a single recessive gene is associated with high pod-shatter resistance in Brassica napus L. 被引量:5
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作者 Wen Chu Jia liu +8 位作者 Hongtao Cheng Chao li li fu Wenxiang Wang Hui Wang Mengyu Hao Desheng Mei Kede liu Qiong Hu 《The Crop Journal》 SCIE CSCD 2022年第3期638-646,共9页
Pod shattering causes severe yield loss in rapeseed(Brassica napus L.)under modern agricultural practice.Identification of highly shatter-resistant germplasm is desirable for the development of rapeseed cultivars for ... Pod shattering causes severe yield loss in rapeseed(Brassica napus L.)under modern agricultural practice.Identification of highly shatter-resistant germplasm is desirable for the development of rapeseed cultivars for mechanical harvesting.In the present study,an elite line OR88 with strong shatter resistance and a lignified-layer bridge(LLB)structure was identified.The LLB structure was unique to OR88 and co-segregated with high pod-shatter resistance.The LLB structure is differentiated at stage 12 of gynoecium development without any gynoecium defects.Genetic analysis showed that LLB is controlled by a single recessive gene.By BSA-Seq and map-based cloning,the resistance gene location was delimited to a0.688 Mb region on chromosome C09.Transcriptome analysis suggested Bn TCP8.C09 as the gene responsible for LLB.The expression of Bn TCP.C09 was strongly downregulated in OR88,suppressing cell proliferation in the pod valve margin.KASP markers linked to the candidate gene were developed.This pod shatter-resistant line could be used in rapeseed breeding programs by direct transfer of the gene with the assistance of the DNA markers. 展开更多
关键词 Pod shatter Lignified-layer bridge BSA-Seq KASP marker RAPESEED
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Accessory Breast Cancer Occurring Concurrently with Bilateral Primary Invasive Breast Carcinomas:A Report of Two Cases and Literature Review 被引量:8
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作者 Jin-yan Hao Cui-cui Yang +9 位作者 Fang-fang liu Yi-ling Yang Shuai li Wei-dong li Ya-qing li Rong-gang Lang Yu Fan Estifanos Paulos Xin-min Zhang li fu 《Clinical oncology and cancer researeh》 CAS CSCD 2012年第3期197-201,共5页
The development of accessory breast tissue,which is found anywhere along the milk line,is attributed to the failure of milk line remnants to regress during embryogenesis.Primary tumors may arise from any ectopic breas... The development of accessory breast tissue,which is found anywhere along the milk line,is attributed to the failure of milk line remnants to regress during embryogenesis.Primary tumors may arise from any ectopic breast tissue.Accessory breast cancer occurring concurrently with primary invasive breast cancer is extremely rare.Two such cases were reported in this article.One was a 43-year-old Chinese female who exhibited bilateral breast cancer(invasive ductal carcinoma,not otherwise specified,IDC-NOS) and an accessory breast carcinoma(IDC-NOS) incidentally identified in her left axilla.The ectopic breast tissue in her right axilla presented with adenosis.The patient was surgically treated,followed by postoperative docetaxel epirubicin(TE) chemotherapy.The second case was a 53-year-old Chinese female with bilateral breast cancer(apocrine carcinoma) accompanied by an accessory breast carcinoma(IDC-NOS) in her right axilla that was also incidentally identified.The patient was surgically treated after three doses of cyclophosphamide epirubicin docetaxel(CET) neoadjuvant chemotherapy,followed by adjuvant chemotherapy of the same regimen. 展开更多
关键词 invasive breast cancer BILATERAL PRIMARY accessory breast cancer occurring concurrently
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Primary Breast Lymphoma (PBL): A Literature Review 被引量:3
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作者 Hua YANG Rong-gang LANG li fu 《Clinical oncology and cancer researeh》 CAS CSCD 2011年第3期128-132,共5页
Primary breast lymphoma is a rare disease. It is mainly found in female patients, the right breast in more frequently involved. The majority of PBL are diagnosed by biopsy or post- operative pathological findings. The... Primary breast lymphoma is a rare disease. It is mainly found in female patients, the right breast in more frequently involved. The majority of PBL are diagnosed by biopsy or post- operative pathological findings. The combined therapy regimen, the main part of which is CHOP chemotherapy, is the main stream. Radical surgery is to be avoided. 展开更多
关键词 BREAST LYMPHOMA DIAGNOSIS clinical characteristics treatment prognosis.
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Stability of Sn-Pb mixed organic–inorganic halide perovskite solar cells:Progress,challenges,and perspectives 被引量:1
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作者 Shaoshen Lv Weiyin Gao +9 位作者 Yanghua liu He Dong Nan Sun Tingting Niu Yingdong Xia Zhongbin Wu lin Song Chenxin Ran li fu Yonghua Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第2期371-404,共34页
The exploration of low bandgap perovskite material to approach Shockley-Queisser limit of photovoltaic device is of great significance,but it is still challenging.During the past few years,tin–lead(Sn-Pb)mixed perovs... The exploration of low bandgap perovskite material to approach Shockley-Queisser limit of photovoltaic device is of great significance,but it is still challenging.During the past few years,tin–lead(Sn-Pb)mixed perovskites with low bandgaps have been rapidly developed,and their single junction solar cells have reached power conversion efficiency(PCE)over 21%,which also makes them ideal candidate as low bandgap sub-cell for tandem device.Nevertheless,due to the incorporation of unstable Sn^(2+),the stability issue becomes the vital problem for the further development of Sn-Pb mixed perovskite solar cells(PSCs).In this review,we are dedicated to give a full view in current understanding on the stability issue of SnPb mixed perovskites and their PSCs.We begin with the demonstration on the origin of instability of Sn-Pb mixed perovskites,including oxidation of Sn^(2+),defects,and interfacial layer induced instability.Sequentially,the up-to-date developments on the stability improvement of Sn-Pb mixed perovskites and their PSCs is systematically reviewed,including composition engineering,additive engineering,and interfacial engineering.At last,the current challenges and future perspectives on the stability study of Sn-Pb mixed PSCs are discussed,which we hope could promote the further application of Sn-Pb mixed perovskites towards commercialization. 展开更多
关键词 Sn-Pb mixed perovskites STABILITY Interfacial defects Energy level mismatch Solar cells
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Preliminary Study on Drug Susceptibility Profile and Resistance Mechanisms to Macrolides of Clinical Isolates of Non-tuberculous Mycobacteria from China 被引量:4
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作者 li fu li Gui lian +7 位作者 PANG Hui liU Hai Can XIAO Tong Yang li Shuang Jun LUO Qiao JIANG Yi WANG Rui Bai WAN Kang lin 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第4期290-299,共10页
Objective Macrolide susceptibility and drug resistance mechanisms of clinical non-tuberculous mycobacteria(NTM) isolates were preliminarily investigated for more accurate diagnosis and treatment of the infection in ... Objective Macrolide susceptibility and drug resistance mechanisms of clinical non-tuberculous mycobacteria(NTM) isolates were preliminarily investigated for more accurate diagnosis and treatment of the infection in China. Methods Four macrolides, including clarithromycin(CLAR), azithromycin(AZM), roxithromycin(ROX), and erythromycin(ERY), were used to test the drug susceptibility of 310 clinical NTM isolates from six provinces of China with the broth microdilution method. Two resistance mechanisms, 23 S r RNA and erm, were analyzed with nucleotide sequence analysis. Results Varied effectiveness of macrolides and species-specific resistance patterns were observed. Most Mycobacterium abscessus subsp. massiliense were susceptible and all M. fortuitum were highly resistant to macrolides. All the drugs, except for erythromycin, exhibited excellent activities against slow-growing mycobacteria, and drug resistance rates were below 22.2%. Only four highly resistant strains harbored 2,058/2,059 substitutions on rrl and none of other mutations were related to macrolide resistance. G2191 A and T2221 C on rrl were specific for the M. abscessus complex(MABC). Seven sites, G2140 A, G2210 C, C2217 G, T2238 C, T2322 C, T2404 C, and A2406 G, were specifically carried by M. avium and M. intracellulare. Three sites, A2192 G, T2358 G, and A2636 G, were observed only in M. fortuitum and one site G2152 A was specific for M. gordonae. The genes erm(39) and erm(41) were detected in M. fortuitum and M. abscessus and inducible resistance was observed in relevant sequevar. Conclusion The susceptibility profile of macrolides against NTM was demonstrated. The well-known macrolide resistance mechanisms, 23 S r RNA and erm, failed to account for all resistant NTM isolates, and further studies are warranted to investigate macrolide resistance mechanisms in various NTM species. 展开更多
关键词 Non-tuberculous mycobacteria Macrolide Drug resistance
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补锂粘结剂羧甲基纤维素锂(CMC-Li)的合成与应用研究
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作者 邱磊 李富 +2 位作者 杨稳 陈允 胡学步 《重庆理工大学学报(自然科学)》 CAS 北大核心 2023年第4期133-140,共8页
以纤维素粉和乙醇锂为原材料,通过IR分析显示成功合成得到羧甲基纤维素锂(CMC-Li)。分别以CMC-Li和羧甲基纤维素钠(CMC-Na)作为锂离子电池负极粘结剂进行研究,发现CMC-Li表现出比较优秀的悬浮和分散性能,不与电解液发生反应,稳定性好。... 以纤维素粉和乙醇锂为原材料,通过IR分析显示成功合成得到羧甲基纤维素锂(CMC-Li)。分别以CMC-Li和羧甲基纤维素钠(CMC-Na)作为锂离子电池负极粘结剂进行研究,发现CMC-Li表现出比较优秀的悬浮和分散性能,不与电解液发生反应,稳定性好。同时,在相同条件下,CMC-Li可以提高电极的压实密度、吸液速率和吸液量,减少极化现象,降低内阻10%左右,减少物理反弹约14.5%,使得充放电比容量提高约1%,剥离强度提高约9.8%,首效提高约2%,循环寿命延长约12%,有着非常优秀的补锂效果。 展开更多
关键词 乙醇锂 羧甲基纤维素锂 粘结剂 补锂效果 锂离子电池
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Complete organelle genomes of Sinapis arvensis and their evolutionary implications 被引量:1
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作者 Shifei Sang Hongtao Cheng +7 位作者 Desheng Mei li fu Hui Wang Jia liu Wenxiang Wang Qamar U.Zaman Kede liu Qiong Hu 《The Crop Journal》 SCIE CAS CSCD 2020年第4期505-514,共10页
Sinapis arvensis,belonging to the genus Sinapis of the family Brassicaceae,has good agronomic characters that make it a valuable genetic resource for crop improvement and is a cytoplasmic source of heterologous cytopl... Sinapis arvensis,belonging to the genus Sinapis of the family Brassicaceae,has good agronomic characters that make it a valuable genetic resource for crop improvement and is a cytoplasmic source of heterologous cytoplasmic male sterility(CMS).In addition,S.arvensis has played an important role in the evolution of the six major cultivated Brassica species involved in the triangle of U.Using next-generation sequencing,we assembled and revealed the gene composition of S.arvensis cytoplasmic genome.The chloroplast genome comprises 153,590 bp,with 112 individual genes,including 4 r RNA,29 t RNA,and 79 proteincoding genes.The mitochondrial genome comprises 240,024 bp,with 54 genes,including 18 t RNA,three r RNA and 33 protein-coding genes.Genome structure and evolutionary analysis indicated that the sequences of the S.arvensis organellar genomes were more similar to those of Brassica nigra and B.carinata than to those of other Brassicaceae species.Four mitochondrial open reading frames displaying chimeric structural features and encoding hypothetical proteins with transmembrane domains may account for the infertility of Nsa CMS previously derived from somatic cell hybridization between B.napus and S.arvensis.These results will not only contribute to utilize the germplasm resource of S.arvensis,and comprehend the evolution of organelle genomes within the Brassicaceae family,but also help to identify genes conditioning the alloplasmic male sterility of Nsa CMS in B.napus. 展开更多
关键词 species. ORGANELLE EVOLUTIONARY
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Increased Risk of Neonatal Pneumonia in Pregnant Women with Atypical Pre-Labor Rupture of Membrane Assessed at Pregnancy Week 39
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作者 li fu Haiyan Pei +4 位作者 Yuefeng Wang Dan Zhang Xiaodan liu Huaizhong Hu Xinghui liu 《Open Journal of Obstetrics and Gynecology》 2024年第4期528-534,共7页
Purpose: Neonatal pneumonia is a major newborn disease with a high morbidity rate. We aimed to evaluate whether atypical prelabor rupture of membranes (PROM) is a high-risk factor for causing neonatal pneumonia in a p... Purpose: Neonatal pneumonia is a major newborn disease with a high morbidity rate. We aimed to evaluate whether atypical prelabor rupture of membranes (PROM) is a high-risk factor for causing neonatal pneumonia in a prospective real-world study. Patients and Methods: A total of 250 pregnant women at pregnancy week 39 were non-selectively recruited. All were examined by PROM and neonatal pneumonia related clinical, bedside and lab tests, including body temperature, blood pressure, increased vagina discharge, posterior vault pooling, abdominal tenderness, WBC count, nitrazine test, amniotic fluid index, Leakection (a sICAM-1 based lateral flow immunoassay) and vagina streptococcus examinations. Increased vagina discharge with a Leakection positivity was adopted as a working criterium for identifying atypical PROM. Neonatal pneumonia was diagnosed based on the clinical presentation and lab tests. Results: Twenty cases of neonatal pneumonia (8.0%) were diagnosed after the deliveries of the 250 pregnant women. In these neonatal pneumonia cases, 12 (16.7%) occurred in 72 deliveries with atypical PROM, 2 (16.7%) in 12 deliveries with typical PROM, and 6 (3.6%) in 166 deliveries with non-PROM. Conclusion: In this real-world study, we find that a systematic screening at pregnancy week 39 was very meaningful in revealing atypical PROM. Moreover, atypical PROM is a major risk factor for neonatal pneumonia. Therefore, an early diagnosis and intervention on atypical PROM could potentially reduce the occurrence of neonatal pneumonia. 展开更多
关键词 Atypical Prelabor Rupture of Membranes Neonatal Pneumonia Soluble Intercellular Adhesion Molecule-1
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基于充电导体模型的水力压裂电磁响应特征分析
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作者 李帝铨 李富 +3 位作者 张乔勋 黄亚 别勇杰 胡艳芳 《石油地球物理勘探》 EI CSCD 北大核心 2024年第1期151-159,共9页
随着中国非常规、超低渗油气资源的大力开发,压裂监测技术迎来重大发展机遇。电磁法在地球物理探测方面具有成本低、时效性强、探测深度大等优点,但面对大深度压裂环境,电磁压裂监测技术的可行性亟须论证。基于充电导体和电偶极源扩散... 随着中国非常规、超低渗油气资源的大力开发,压裂监测技术迎来重大发展机遇。电磁法在地球物理探测方面具有成本低、时效性强、探测深度大等优点,但面对大深度压裂环境,电磁压裂监测技术的可行性亟须论证。基于充电导体和电偶极源扩散电磁场理论,首先构建了不同深度和不同长度下的裂缝压裂模型,分析了各模型的地面总场及异常场的电磁响应特征。分析结果表明:利用井地电磁法进行压裂监测时,观测总场对裂缝长度增加引起的电磁响应不敏感,异常场存在低值带;深度为4000 m时,电磁异常小于1%,深度越大异常场衰减越严重,且相邻测点间异常场的绝对值与深度呈负相关,电磁法压裂监测技术难以兼顾探测精度与探测深度。然后,通过建立压裂监测物理模型,分析实测数据电磁异常曲线特征,验证了理论计算的正确性。最后,结合前人理论成果和实践经验,提出了一种井中激发—地面接收的测网式电磁法压裂监测观测系统,对测区范围与测点间距进行合理约束,系统具有野外施工简捷、监测深度大等优势,为电磁法压裂监测提供了新的发展方向。 展开更多
关键词 充电导体 电磁监测 探测深度 低值带 水力压裂
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向下短波辐射差异对草甸化草原地表辐射平衡的影响
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作者 李甫 周秉荣 +2 位作者 王力 马文哲 霍金虎 《高原气象》 CSCD 北大核心 2024年第1期217-226,共10页
基于向下短波辐射分位数,对中国气象局海北牧业试验站2014年9月至2020年12月四分量辐射观测数据按月进行分组。分析了向下短波辐射差异对草甸化草原辐射平衡的影响,为明晰不同光照条件下辐射平衡变化和成因提供了依据。结果表明:在相同... 基于向下短波辐射分位数,对中国气象局海北牧业试验站2014年9月至2020年12月四分量辐射观测数据按月进行分组。分析了向下短波辐射差异对草甸化草原辐射平衡的影响,为明晰不同光照条件下辐射平衡变化和成因提供了依据。结果表明:在相同月份中,不同光照条件下地表接收的向下短波辐射呈现出极显著的对数变化趋势,组间差异超过了季节之间的差异。不同光照条件下向上短波辐射和大气长波辐射也表现出较大差异,其中大气长波辐射差异主要与空气湿度以及云量差异有关。随光照条件的增加,地表接收的净短波辐射增多,支出净长波辐射也增多。所以不同光照条件下净全辐射与向下短波辐射的比例相差不大。不过,光照条件差异会对向下短波辐射与净全辐射的关系模型产生影响。 展开更多
关键词 四分量辐射 向下短波辐射差异 草甸化草原 辐射平衡
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1例输入性类鼻疽病例病原学特征及耐药分析
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作者 梁志超 乔富宇 +9 位作者 王小梅 李爽 窦相峰 曲梅 吕冰 李夫 金昊源 张新 任振勇 林长缨 《首都公共卫生》 2024年第3期181-184,共4页
目的 描述1例境外输入类鼻疽患者的流行病学特征、实验室诊断和耐药性特征,为类鼻疽的监测、诊断治疗及防控提供依据。方法 收集患者流行病学调查信息,采集患者全血、血清、尿液、皮疹部位涂抹拭子及肺泡灌洗液样本进行细菌分离培养。... 目的 描述1例境外输入类鼻疽患者的流行病学特征、实验室诊断和耐药性特征,为类鼻疽的监测、诊断治疗及防控提供依据。方法 收集患者流行病学调查信息,采集患者全血、血清、尿液、皮疹部位涂抹拭子及肺泡灌洗液样本进行细菌分离培养。培养物采用生化试验进行鉴定,使用肉汤稀释法药敏试验分析耐药情况。结果 患者皮疹部位涂抹拭子及肺泡灌洗液样本经过72 h分离培养,从皮肤涂抹拭子及肺泡灌洗液的样本中分离到2株菌株,经生化鉴定确定为类鼻疽伯克霍尔德菌。耐药性分析显示,该菌株对头孢唑啉、头孢噻肟、庆大霉素、多黏菌素B、氨曲南和链霉素6种药物耐药,患者经治疗后痊愈出院。结论 疾病诊断应关注患者旅行史和接触史,细菌性疾病应关注菌株耐药情况。 展开更多
关键词 类鼻疽 类鼻疽伯克霍尔德菌 分离鉴定 耐药性
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职业教育跨境推广与国际产能合作耦合系统架构
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作者 李富 李卓然 王湘蓉 《宁波职业技术学院学报》 2024年第4期16-23,共8页
职业教育跨境推广与国际产能合作需加强耦合。职业教育跨境推广呈现出校企合作境外办学形式和办学品牌多样化、校企合作人才推广渠道趋于丰富、校企合作专业标准和专业课程推广数量增多等特点。但同时国际产能合作视域下职业教育跨境推... 职业教育跨境推广与国际产能合作需加强耦合。职业教育跨境推广呈现出校企合作境外办学形式和办学品牌多样化、校企合作人才推广渠道趋于丰富、校企合作专业标准和专业课程推广数量增多等特点。但同时国际产能合作视域下职业教育跨境推广还存在一些问题,如国际化技能竞赛与国际产能合作衔接桥梁需要架构、科学研究服务国际产能合作能力有待提升、数字化服务国际产能合作领域亟待加强等。基于现实性、前瞻性和数字化等需求,需要架构职业教育跨境推广与国际产能合作耦合系统,并从激励机制、国际融入、智库建设、行业标准平台搭建、数字化引领、风险防范等维度,构建耦合系统实施的保障机制,推进职业教育服务国际产能合作效能的稳步提升。 展开更多
关键词 职业教育 跨境推广 国际产能合作 耦合
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SESN2 ablation weakens exercise benefits on resilience of gut microbiota following high-fat diet consumption in mice
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作者 Chunxia Yu Peng Zhang +2 位作者 Sujuan liu Yanmei Niu li fu 《Food Science and Human Wellness》 SCIE CSCD 2023年第6期1961-1968,共8页
Gut dysbiosis is associated with several pathological processes.Previous study showed that regular exercise can protect against dysmetabolism in high-fat diet(HFD)fed mice through butyrate-SESN2 pathway,and SESN2 abla... Gut dysbiosis is associated with several pathological processes.Previous study showed that regular exercise can protect against dysmetabolism in high-fat diet(HFD)fed mice through butyrate-SESN2 pathway,and SESN2 ablation weakened the protective effects of exercise.Here,we investigated whether SESN2-defi ciency suppresses the exercise response to microbiota composition and subsequently reduces the benefi ts of exercise on dysmetabolism induced by HFD.Wild type(WT)and SESN2^(-/-)mice were assigned to fi ve-groups,fed with either normal chow or HFD and with or without exercise training for 15-week.Fecal microbiota composition and function were assessed by 16S rRNA sequencing.The sequencing results showed that SESN2^(-/-)mice displayed differed microbiome profile from WT mice.Exercise enriched the microflora diversity and increased the benefi cial microbial species in WT mice,and SESN2 ablation weakened the benefi cial effects of exercise on microbial resilience following HFD consumption.Moreover,network analysis revealed that exercise increased correlation density and clustering of operational taxonomic units in WT mice only.KEGG demonstrated that some dominant metabolism-related enzymes and modules increased in SESN2^(-/-)mice.Our results indicated that the effects of exercise on metabolism are associated with the perturbations of gut microbiota composition and function,suggesting that SESN2 contributes to maintain metabolic homeostasis. 展开更多
关键词 EXERCISE High-fat diet Sestrin2 OBESITY Gut microbiota
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